If you do not have a light source for your newt tank, the following plants can still be used.
Java moss, java fern, willow moss, and the toughest of all plants Anubias.
I use these plants in all of my aquatic set ups.
No special care or feeding is needed for the above plants to flourish, and all but the Anubias are eagerly used for newts when egg laying.
If the tank has a growlight, then many more types of plant can be used, but try to steer clear of any plants needing a lot of light or specialist feeding.